1. Field of the Invention
The present invention is related to a file management system and method, particularly for the system and method of using file encryption technologies, applying file access control to the encrypted files, and recording the corresponding file usage information.
2. Description of the Related Art
With the development of Internet and portable devices (e.g., USB pen drive, mobile phone, and so on.), electronic files (e.g., Microsoft Word, Adobe PDF, and so on) become more and more popular and convenient for information delivery. Instead of exchanging or transmitting files via humans and transportations, the information delivery duration is significantly reduced by transmitting the electronic files via Internet and portable devices.
Besides, the electronic files may be uploaded to an Internet hard drive by their owner, and these files can be downloaded anywhere when the owner can connect to the Internet hard drive via the Internet. However, a cracker will have a chance to download the electronic files from the Internet hard drive and transmit the downloaded files to anyone without an agreement of the owner.
In many enterprises, files are generally stored in electronic form and some of these electronic files may contain confidential information, such as architectural drawings of the construction industry, electronic circuit diagrams of the IC design house, source codes of the software design house, songs and commercial content of the cultural and creative industry, and personal information of the financing industry. Once the computers used to store these confidential files are hacked, the confidential files may be transmitted arbitrarily to other people by the cracker. The above cases always have a great damage on the corporation's CI (Corporate Image), goodwill, and revenue.
Furthermore, as comparing the usages of electronic files and conventional hardcopies on paper, the electronic files are easy to be duplicated and delivered. As a result, the hackers and competitors can easily retrieve the confidential content of electronic files via illegal methods, the owner of the electronic files cannot prevent and control damages caused by these security breaks in time.
The file encryption is the most common technique to protect the confidential information stored in the electronic files. When the owner transmits an encrypted file to a user, the user needs know that how to decrypt the encrypted file. Therefore, the encrypted file cannot be used by a user without knowing the password. In general, most of users use simple passwords to encrypt files. It leads to that the encrypted files can be easily hacked by the crackers. Furthermore, after getting the passwords, the user may arbitrarily use the encrypted file and transmit the encrypted file to other people without the agreement of the owner. When the encrypted file is disclosed to the public, it is hard to clarify the responsibility of disclosing the encrypted file.
Furthermore, when the encrypted file is transmitted to the user and the corresponding password is told to the user, the owner cannot control the usage of the encrypted file any more. Then, the corresponding password and content of the encrypted file may be disclosed by the user, so that the encrypted file is leaked. Thus, when the encrypted file is decrypted using the password, the user can edit or modify the content of the encrypted file and transmit the modified file with incorrect information to other people. Then information corresponded to the content of the encrypted file may be transmitted with incorrect information. Once someone get the password to decrypt the encrypted file, the owner cannot control the usage of the encrypted file, so that the encrypted file does not have confidential. In other words, when the owner transmits the encrypted file to the user, the owner cannot control where the encrypted file is transmitted or control time limitation of the encrypted file. Therefore, the protection technique of electronic files needs to be further improved by reducing the risk of file transmission and enhancing the security of the stored files.